Etymology The verb is from “The Terrible Sea Lion”, a 2014 strip in the webcomic Wondermark, in which a character expresses a dislike of sea lions and a passing sea lion repeatedly, intrusively asks the character to justify this.
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Internet, Derogatory To intrude on a conversation with probing questions in an attempt to engage in unwanted debate, usually disingenuously as a form of harassment or trolling.
There, Peggy speaks for every angry marginalised person who’s ever been sealioned or tone-policed in a disagreement.2015 January 28, Andrew Wheeler, “Agent Carter’ Recap, Episode 4: The Blitzkrieg Button”, in Comics Alliance, archived from the original on 03 Feb 2015:
The purpose of sealioning never to actually learn or become more informed.2015 March 24, Sarah Seltzer, “Beyond Mansplaining: A New Lexicon of Misogynist Trolling Behaviors”, in Flavorwire, archived from the original on 25 Mar 2015:
2 more examples
I can attest to reactionary right-wing trolls being the black belt masters of Internet pile-ons, or as Wondermark has indelibly dubbed the practice, “sealioning.”2015 April 1, Arthur Chu, “Trevor Noah and the Toxicity of Twitter: A Cocktail Party Conversation That’s Being Refereed”, in The Daily Beast, archived from the original on 05 Nov 2017:
Popular definitions of harassment also extend to “sealioning” — a recently coined term based on an Internet comic, “The Terrible Sea Lion” — which seems to mean little more than unwelcome attempts to engage someone in debate.2015 November 19, Cathy Young, “The dangers of going too far to curb online harassment”, in Washington Post, archived from the original on 20 Nov 2015:
Etymology The verb is from “The Terrible Sea Lion”, a 2014 strip in the webcomic Wondermark, in which a character expresses a dislike of sea lions and a passing sea lion repeatedly, intrusively asks the character to justify this.
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Alternative, Uncommon Alternative form of sea lion.
Randi's list is a key reason I've been able to continue to use Twitter, as it prevents relentless ideological sealions from crowding my mentions.2014 December 2, Glenn Fleishman, “Twitter takes aim at trolls—and promises more”, in Boing Boing, archived from the original on 03 Dec 2014: